The preservation of the sacred and universally recognized values of improvisational theatre. It applies to both the performance of improv and the conduct of an improv troupe.
Man #1: Hey man, I thought of a really funny joke. I might save it for a show
Man #2: INTEGRITY OF IMPROV!
Man #1: Whoa, calm down! I'll forget it. But can I bring my friend to the party AFTER the show?
Man #2; INTEGRITY OF IMPROV!